[openssl/openssl] 70d9e6: apps/speed.c: Wait for generated children

[openssl-machine]

  Branch: refs/heads/openssl-3.0
  Home:   https://github.com/openssl/openssl
  Commit: 70d9e64b634673257ab64561e1c04ee8d1d4a24a
      https://github.com/openssl/openssl/commit/70d9e64b634673257ab64561e1c04ee8d1d4a24a
  Author: Juergen Christ <jchrist at linux.ibm.com>
  Date:   2022-08-31 (Wed, 31 Aug 2022)

  Changed paths:
    M apps/speed.c

  Log Message:
  -----------
  apps/speed.c: Wait for generated children

In multi-mode, speed fork()s off several children but does not wait for them.
On Linux, this leads to wrong accounting information of getrusage used by
tools to extract running time and page faults.

Wait for every children and check the return code and termination signal.

Signed-off-by: Juergen Christ <jchrist at linux.ibm.com>

Reviewed-by: Paul Dale <pauli at openssl.org>
Reviewed-by: Tomas Mraz <tomas at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/19093)

(cherry picked from commit 56233ba8574c01b3912cf662335fedaabc7faec2)